How Fabry Disease affects the body
Our bodies contain thousands of active substances called enzymes. In people without Fabry disease, the enzyme alpha-galactosidase A (pronounced al-fa-ga-lak-toe-si-daze a), or alpha-GAL, helps the body to break down a fatty substance called globotriaosylceramide (pronounced glow-bow-tri-oh-syl-ser-a-mide), or GL-3.
People with Fabry disease are missing or have insufficient amounts of the alpha-GAL enzyme, which is important in the healthy functioning of organs.
The alpha-GAL enzyme is responsible for removing a fatty substance, GL-3, from cells throughout the body. Without enough of this enzyme, the GL-3 substance builds up in cells. GL-3 build-up in kidney cells may cause severe kidney problems, including kidney failure. People with Fabry disease may experience a wide range of signs and symptoms, including severe conditions such as kidney failure, heart problems, and stroke.
Because Fabry disease is rare and not always well recognised, its symptoms are sometimes overlooked or attributed to other more common conditions. There are, however, a number of signs and symptoms that people with Fabry disease typically experience:
- Burning, tingling pain in the hands and feet
- Pain radiating throughout the body
- Impaired sweating
- Heat/cold intolerance
- Skin rashes (angiokeratomas)
- Corneal whorling (pattern on the cornea of the eye – generally does not affect vision and can only be seen using special eye exam equipment called a slit lamp)
- Hearing problems
- Gastrointestinal problems, such as diarrhoea or vomiting
- Heart problems (including enlarged heart and heart valve problems)
- Kidney problems
- Nervous system problems, such as stroke
- Psychological issues, such as depression
Inheritance, Diagnosis & Treatment
A father with Fabry disease (Affected Father) will pass the gene onto all of his daughters and none of his sons (see the figure below). The Fabry gene is located on the X chromosome and a man will only pass his X chromosome (which carries the Fabry gene) on to his daughters. His daughters will likely not have Fabry disease but will be Fabry carriers. This is because the daughters' other X chromosome will likely carry a healthy gene that is capable of making alpha-GAL. However, some female Fabry carriers experience symptoms of Fabry disease.
A test, called an enzyme assay, measures the amount of alpha-GAL enzyme activity in the blood. If the enzyme is low or absent, a diagnosis of Fabry is confirmed.
An enzyme replacement therapy is available to treat this disease.